174 is probably going to be the easier weight, as he is the highest ranked
returning wrestler from last years NCAA tourney. At least that is what they are projecting. Valencia is projected to move up to 184, Hall has been rumored to take an Olympic Redshirt (which I don't understand), Amine is taking an Olympic Redshirt, and Lewis graduated.
The top two are still yet to officially declare their intent, but those are the well respected rumors. So in addition to it being an touch cut for DM, it would make more sense to have him to stay at 174. At 165 he would have to battle Joseph and probably Bull (Marineli, i don't think he Olympics).
The Olympic does make sense for Lewis though, as it will distance himself from both Joseph and Marineli. In 2021 he won't have to see Joseph, and only have one more year of Marineli.